Electric switch



1 V 0 I "W 927 H. J. L FRANK ELECTRIC SWITCH I Filed Sept. 17 1921 s Shoots-Sheet 1 INVENTOR.

l A TTORNEY.

June 28, 9 7 J, FRANK ELECTRIC sw lTca Filed Sept. 17 1921 I 1 3.5hOQtS-Sh00t I I N VEN TOR.

ATTORNEY.

June 28 1927.

I H. J. L. FRANK ELECTRIC SWITCH Filed Se t/r1.- 1921 3 Shoots-Shoot 3 INVENTOR. 4

X. FZ'WWK W $924M,

A TTORNEY.

Patented June 28,1927.

UNITED STATES PATENT OFFICE.

HARRISON J'. L. FRANK, OF DETROIT, MICHIGAN, ASSIGNOR T MUTUAL ELECTRIC AND MACHINE COMPANY, OF DETROIT, MICHIGAN,

VIRGINIA.

.A. CORPORATION OF WEST mnc'rnrc swrrcrr.

Application filed September 17, 1921. Serial 501,968.-

This invention relates to the construction of that type of switch boxes in which all the contacts are entirely enclosed but may be operated by means of a handle on the outside of the box, and its object is to provide a simple and reliable construction which may be locked against operation or against access as may be desired and in which a plurality of rigidly connected l0 switches are operated simultaneously.

This invention consists in a box in which switch members are mounted on a base of insulating material, the switch members consisting of knife-blades, pivots therefor and contacts to receive the knife-blades, said knife-blades being. rigidly connected by means of a metal bar covered with a shell of insulating material, and an operating member journaled in opposite sides of the box with the line of its journals parallel to the line of pivots of the switches, the operating member constituting a bail between its journals and the connecting bar having its ends formed to fit around the ends of the bail.

It further consists in forming one side of the box with a slot to permit the operating member to be inserted and in a stop plate formed with a bearing for the operating member and with stops to limit its movement.

It also consists in the details of construction illustrated in the accompanying drawings and particularly pointed out in the claims.

In the accompanying drawings, Fig. 1 is a front elevation of this improved box with the cover open. Fig. 2 is a side elevation thereof. Figs. 3 and 4 are sections on the lines 33 and 4-4 of Fig. 1 respectively. Fig. 5 is a section on the line 5-5 of Fig. 2. Fig. 6 is a section on the line 6-6 of Fig. 11. Fig. 7 is an elevation of switch-blade connector bar. Fig. 8 is an ele vation of a switch blade. Fig. 9 is a perspective view of a connector bar with a blade attached thereto. Fig. 10 is a perspective of a stop-plate. Fig. 11 is a side elevation of a slightly modified type of switch box. 30 Fig. 12 is a section on the line .12-12 of Fig. 1. Fig. 13 is a front elevation of this switch provided with a modified type of connecting bar between the knife blades.

14' is a section on the line i l-14 of 55 Fig. 13. Figs? 15 and 16 -are elevations of the blank for the a knife edgedesignedfor this type of switch, Fig. 16 showing the connector bar in position. Fig. 17 is a perspective of this connector bar. Fig. 18 is a perspective of this type of connector bar with a. metal plate connected to it to engage the operating member. Fig. 19 is an elevation and Fig. 20 a perspective view of another form of operating member. Fig. 21 is a detail of a bearing plate.

Similar reference characters refer to like parts throughout the several views. The box in which the switch is mounted 1s preferably rectangular of any desired proportions and size, that shown having a back 1, sides 2 and 3, and ends 4 and 5. The ends are notched and closed by the usual end plates 6 having struck-up tongues 7 to secure these plates in position. The cover 8 is hinged to the side 2 and9, and when-closed down, prevents removalof these plates. A

resilient latch 10 secured to the side 3 is adapted to extend through a slot in the cover and has a hole 11 to receive the hasp 12 of a padlock. It also preferably has a struckup detent 13 which normally holds down the cover.

Secured to the back 1 by the screws 14 is a block 15 of non-conducting material such as slate or porcelain, to which .are secured the terminals 16 and 17 for the knife-blades 18, the sockets 19 for the fuse plugs 20 and the terminals 21 for the service wires 22. The line wires 23 connect to the terminals 16. A connection 24 may be attached to the side 3 to ground the box. A connector 50' (Fig. 12) is attached to each central terminal 51 of the fuse socket 19 and to each support 16 of the knife-blades 18, a screw 52 securing this support in position. Wax 53 or other sealing material prevents access to this connector. The construction thus .far described is well known.

In order to open and close the switches by swinging the knife-blades 18, I prefer to form a connector bar by stamping out a blank 25 having arms 26 at its ends, and Wind the same with a sheet of fusible insulating material 27, such as paper impregmated with shellac. This connector bar and its winding are then baked to fuse the gum and the bar is then slipped into the notch 28 in the knife blade between the fingers 29 thereon which are then pinched onto the bar. The fused insulation is very hard and limit the movements of the handle and the permanently united to the bar so that there is little danger fingers are brought together-as shown in The operating device for the switch comprises a crank 30, two journal portions 31 and 32 and a handle 33. a The side 2 is formed with a'hole to receive the journal 31, but the side 3 is formed with a slot 34 through which the crank 30 may be introduced; A stop-plate 35 is. formed with a drawn bearin" 36 for the journal 32 and is slipped into p ace before the bail -is inserted through the slot 34. The plate 35 is preferably formed with a dowel- 36 to extend into this slot, as indicated in Fig. 5, to posi-' tion the plate which is spot-welded into place after the parts are assembled. When the operating crank and .the pivots of the knife-blades are out of alinement, the arms 26 on the connector bar 25 have slidingengagement with the crank arms 41.

The stop-plate has stops 37 and 38 to switch members. The stop '37 is preferably formedwith a slot 39, sufiici'ently long to receive a series of padlock hasps which will extend around the operating handle and pflevent the switch being closed without the owledge' of all those concerned, such as the lineman, foreman and inspector. These stops 37 and 38 are positive and cannot get out of order, an important factor in devices of this character.

I prefer to assemble the box and operating handle and hail including the stop plate and enamel the assembled structure. The

end plates and connector bar are enameled separately and the latter then attached to the knife-blades, after which the switch is assembled and inserted and secured within was the box, the arms 26 being curved if desired as" indicated in Figs. 3 and 4. These arms 26 are notched or forked to engage the crank arms 41 of the operating crank.

Instead of a longitudinal slot 34, the side 3 may be formed with a slot 42 at right angles to its edge to permit free introductionfof the journal portion 32 of the operatmg device. In this case the stop-plate 43 may be'formed with an extension 44 to cover this slot and with a dowel 45' to fit the slot to. osition the plate. .This plate may also be ormed with small dowels 46 to fit holes 47 in the. side 3 to position the plate before it is spot welded into position. An additional pair of dowels are indicated by the small circles 48 in Fig. 11 at each side of the slot indicated by the dotted lines 49, which dowels fit into holes in the metal of the side of the boxand thus bridge this slot. The switch mechanism and the operatin device may be the. same as above describe In Fig. 1 I have shown springs 50 ex tending from the connector bar 25 to the of injury thereto when the operating crank which normally holds the shoulders 51 .at the lower ends of the notches- 52 against the side arms 41 .of the crank. When however theswitch is to be opened,

the friction of the knife bladein the con- I tacts 16 is such as to permit'the side arms to move up to the shoulders 53 against the tension of these springs. Continued movement of the crank moves the knife blades out of engagement. with these contacts, and

at the instant such engagement is broken the springs act to accelerate the movement of and break the are at the lation a solid connector bar 55 of insulating material may be employed. This bar is preferably formed with grooves 56 to receive the ears 57 on the knife blades 58 and the ends of these cars when bent down as shown in Fig. 16, secure the bar to the knife blades.

In Figs. '13 and 14 a connection is shown which is available to cause the crank 59 to swing this bar 55. It consists of a plate bent to constitute a cylinder 60 to receive the side arm 61 of the crank and two ears 62 between which the end of the connector barextends.

In Fig. 18 a forked plate 64 is shown engag ing the side arm "65 of the operating crank, this plate having clamping fingers 66 and 67, the former being bent into one of the grooves 56 of the bar 55.

Instead of forming the operating crank of a single piece of round metal it may be sheared from a flat plate and bent to constitute the crank 70 having side arms 71 from which the ears 72 extend on each side of the ends of the bar 55. The ends of the plate are bent to form journals 73, one of which may be made long enough to receive the operating handle 74. The same stop plate 35 with its sto ln s may be used to provide a bearing1 or t e journal which extends into. the andle 74.

Instead of having the bearing adjacent journal of the operating crank tending outwardly, from the bearing late 35, as does the part 36 in Fig. 6, this ea ing ma extend inwardly, as does the part 76 in ig. 21, in which case the slot in the side of the box is made large enough to receive this hearing.

The proportions and details of the several parts of this device may all be changed by those skilled in the artwithout departing'from the spirit of my invention as set forth in the following claims.

I claim 1. In combination, stationary switch con tacts, movable knife-blade members adapted to engage therewith and formed with pairs of fingersalong one edge, alined pivots for said knife-blade members, a metallic connector bar having forked ends and a shell of for the insulation adapted to be received between said fingers which are closed onto said bar and insulation, and an operating crank for said knife-blade members comprising side arms adapted to be slidably received in the forked ends of the connector bar.

2. In combination, stationary switch contacts, movable knife-blade members adapted to engage therewith, alined pivots for the knife-blade'members, a flat connecting bar and a shell of insulating material thereon, said knife'blade members having pairs of fingers between which said bar is received and which are closed around the bar and the insulation thereon, an operating crank consisting of a pair of arms, a cross bar, and a handle to swing the crank, said connecting bar being formed with forked ends to engage said crank arms to be swung thereby. 20 p 3. In combination, stationary switchcontacts, movable knife-blade members adapted to on age therewith, alined pivots for the knifelades, a metallic connector bar and a shell of insulation thereon attached to the knife-blades a distance from their pivots,

- and a crank having two crank arms whose axis is parallel to that of the knife-blades,

said connector bar having forked ends slidably engaging the crank arms to be actuated thereby to swing the knife-blades.

4. In combination, stationary, switch contacts, movable knife-blade members adapted to engage therewith, alined pivots for the knife-blades, a connector bar attached to "the.

knife-blades a distance from one end and insulated therefrom, and a crank having" two crank arms engaged directly by the ends ofthe connector bar whereby the knife-blades may be swung to open and close the switch.

5. In combination, stationary switch contacts, movable knife-blade members adapted to engage therewith, alined pivots for the knife-blades, a connector bar-and a shell of insulating material composed of a convolutely wound strip of fibrous material and plastic insulation secured to said bar, said knife-blades having slots in their upper edges a distance from their pivots to receive the connector bar and the insulation thereon and also having-fingers adapted to be bent togetherover said connector bar to hold it in position, and means engaging the ends of the connector bar to swing the knife-blades.

6. In combination, an electric switch and the casing therefor having opposite side walls, a switch operating member comprising' a crank within the casing and a handle without the casing, and a stop plate on the operating member between the handle and crank providing a bearing for said operating member and having two integral rigid stops extending from its edges into the path HARRISON J. L. FRANK. 

